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Why do mutations makes it difficult to create a vaccine ? (4 marks - has the potential to be worth more in an exam)

If the mutation rate is high then this can change the DNA composition of the cells. If the DNA changes then so do all the protiens in the cell. This is becauase DNA codes for all the protiens in the cell. Th...
MP
Answered by Muhammad P. • Biology tutor
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An enzyme catalyses only one reaction. Explain why.

Enzyme has a specific active site. Only one substrate will fit the active site.
AM
Answered by Amy M. • Biology tutor
8262 Views

Describe how insulin is secreted from beta cells in the Islets of Langerhans

Insulin is released in response to high blood glucose concentrations. High blood glucose concentrations means glucose is taken up by the beta-cells in the Islet's of Langerhans and is respired to produce ATP...
TD
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Define the term 'phylogeny', how it is related to classification of species, and what kind of evidence is used in phylogenetics. (3 Marks)

Phylogeny is the evolutionary relationships between different species. Species within the same taxonomic group have shared phylogeny (i.e. they have a common ancestor). (1) Phylogeny is what taxonomic classi...
MY
Answered by Mary Y. • Biology tutor
16594 Views

How does crossing over occur during meiosis?

Genetic variation is important because it allows natural selection to act on the population. Individuals that inherit advantagous alleles are more likely to survive and successfully reproduce. Crossing over ...
TA
Answered by Tamara A. • Biology tutor
16730 Views